User guide# User guide Introduction Initialize the Simulation State Initialize the Simulation System Run the Simulation Saving the Simulation The Simulation State State Creation Understanding Positions: pos, pos_c, and pos_p Modifying State Attributes Extending the State Merging Two States Stacking States for Trajectories or Batches Trajectories of Batches Utilities The Simulation System System Creation A note on static methods Configuring the System Manually swapping a submodule Time stepping Trajectory rollout Batched simulations with vmap